1. Field of the Invention
Aspects of the present invention relate to an organic thin film transistor (organic TFT), a flat panel display apparatus having the organic TFT, and a method of manufacturing the organic TFT. More particularly, aspects of the present invention relate to an organic TFT from which a patterning effect of an organic semiconductor layer can be obtained, a flat panel display apparatus having the organic TFT, and a method of manufacturing the organic TFT.
2. Description of the Related Art
TFTs are used in flat panel display apparatuses such as liquid crystal display devices, organic electroluminescent display devices, and inorganic electroluminescent display devices. In such devices, TFTs may be used as switching devices that control the operation of pixels and as operating devices that operates the pixels.
A TFT includes a semiconductor layer having source and drain regions and a channel region, a gate electrode insulated from the semiconductor layer and located in a region corresponding to the channel region, and source and drain electrodes respectively contacting the source and drain regions.
Recently, it has become desirable for flat panel display apparatuses to have slimness and flexibility.
To achieve flexibility in display devices, many attempts have been made to use plastic substrates instead of conventional glass substrates. When a plastic substrate is used, high temperature processing cannot be used but instead, low temperature processing is required. Accordingly, conventional silicon TFTs, which require high temperature processes for their formation, cannot be formed on plastic substrates.
To address this problem, organic semiconductors ithat can be processed at low temperatures have been developed, and thus, low cost TFTs on flexible substrates can be realized.
However, to form an active channel of a TFT, patterning is required, and organic semiconductors cannot be patterned using conventional patterning methods such as photolithography. When the organic semiconductor is patterned using a conventional etching method in which wet and dry etching processes are mixed, the organic semiconductor can be damaged.
On the other hand, if the organic semiconductor layer of a TFT is not patterned, the organic semiconductor layer can cause cross-talk with electronic components such as adjacent wires, other TFTs, or capacitors, resulting in a leakage current and reducing the device characteristics.
Accordingly, there is a need to develop a new method of patterning organic semiconductors.